cyl. 5 missfire. help!

[93PONY]

hello, i have an 03 v6. i keep getting a cyl.5 missfire code along with above 1000k missfire code. so far i have replaced the plugs, replaced the coilpack, replaced all spark wires, and the cam syncronyzer with still the same problem. it only occures under load or if im cruising under 2000k, if i floor it or if i'am cruising at highway speeds it dosnt act up as bad. will kinda backfire/hiccup at times and then take off like nothing is wrong, other times it bogs down so much it seems like its just going to quit on me, then it picks up again. i have noticed that i barely have any exhaust comming from the drivers side tail pipe. would a pluged up muffler cause this?

 

[MustangLX-5.0]

Do you have a true dual exhaust setup? Just wondering because you said exhaust was barely coming out drivers side tailpipe. Now if you don't have dual exhaust; then I would immediately suspect an exhaust leak somwhere.

Sounds like you may have a stuffed up injector on cylinder 5. It's not compensating like the rest when higher fuel demand is required. Have you had fuel injection cleaning done in a while? You may be due for it.

When you replaced the plugs, did you notice anything unusual about the plug in cyl. 5 such as unusual color or odor? Oil, coolant ...excessively black or chalky white? Any smoke from the exhaust?

How many miles on this stang?

 

[93PONY]

only about 50,000 on it, i do have true duels no cats with flows. all plugs looked fine. whats a good do it yourself way to clean an injector? or should i just try replacing it? no smoke from exhaust. is it possible i messed up the timing when i changed out the cam snycro? if so can it be timed by me, or does it need to be hooked up to a computer?

 

[MustangLX-5.0]

If you would've messed up the timing, it would be noticeable on all cylinders, not just specifically missing on one. True duals, then it's definately an injector issue. Probably some deposits lodged in from that cylinder running rich ( for some reason) or it just happened to be the first one to get crapped up. Injector shouldn'tt need replacement. You just need a good injector cleaning done. There is no good DIY way to clean injectors. Even if you remove them and spray/soak the end of each injector in cleaning agents (which I tried once and learned..doh!), it won't do much good. The cleaning has to be run directly through the fuel lines and pass through the injector nozzles. You can either buy the small canister + fittings and compressor and then learn how do do it yourself (not hard but those canister kits are expensive and must be bought through high end tool companies like Matco Tools ..SnapOn etc)... or you can take it to a well known reliable shop and pay for an induction service.

And the timing should be fine. There are no adjustments needed as it's auto done by the PCM. You also can't adjust it unless you have either a special scan tool to re-program the timing settings or get an aftermarket coilpack/ignition that has adjustable timing, which would probably need a reprogram of the PCM.

I'm going to rule out cyl. head problems. An 03 with only 50K+ miles ..its highly unlikely for head gasket problems at such an early mileage. Ford worked out most of those issues with older models.

 

[93PONY]

code p1336

ok ran the scanner and i keep getting code p1336
manufacturer control ignition system or missfire.
here are the specs that i got from my scanner

engine rpm- 1711 rpm
load value- 25.4%
coolant temp- 176*f
short term fuel trim 1- 7.8%
longterm fuel trim 1- 0.8%
short term fuel trim 2- 3.1%
long term fuel trim 2- 2.3%
short term fuel trim 3- 22.6%
long term fuel trim 3- -96.7%
long term fuel trim 4- 85.9%
short term fuel trim 4- -61.6%
vehicle speed- 37mph
fuel rail pressure- 264 kpag
fuel system 1- closed

so far i have replaced the plugs, wires, coil pack, seafoamed the engine and changed oil. before i got this code i kept getting a cyl. 5 missfire code. now im getting this one. any help would be great
__________________

 

[MustangLX-5.0]

I have an idea of what it might be. Could possibly be the cam synchro out of sync with the crank sensor. You did replace it, now that I double checked, the synchro has to be put in sync with the crank sensor. And I think it takes a special tool for that.

Did you have the misfire before you replaced the cam sensor? dont make sense to misfire on only one cylinder for an out of sync issue. The short term fuel trim on bank 1 does definately indicate a rich condition on the drivers side. Although I dont understand what bank 3 and 4 could be. Odd that theres a 3 and 4.


Need to try something. You'll have to reset the PCM after this so..

Unplug the cam sensor and drive it around. See if any of the symptoms still occur. Youu will notice a slight throttle hesitation with the cam sensor unplugged but it should run fine without it. Don't leave it like this, just checking to verify if the cam is actually out of sync. If it runs better without it, then it's out of sync. I'll see if there is a way to avoid having to take it in to a dealer or shop to have it sync'd up.

If you had this problem before the syncro was replaced, chances are you mightve cleared some of it up with the seafoam. pull the sensor and test for several miles first.See what happens.

 

[93PONY]

ok will try that, it seems fine while driving now but i still keep getting that code. it started about 3 weeks after i did the cam syncro. changed it due to is squealing really bad.

 

[93PONY]

ok unplugged sensor and drove around the block, still getting the p1336 code. didn't notice any drivability issues though. will leave it unplugged for a little to see what happens

 

[96sleeper]

If your problem isnt fixed it might be the Ecu once it throws a code and keeps throwing it will try to compensate for the prob mine dide the same but it was a number 4 misfire and a new ecu fixed it